In tunnel mining, movable (mobile) mining machines have long been known with which a tunnel shaft can be driven forwards particularly also in hard rock. Corresponding tunnel boring machines, which have at the front side of a machine frame a cutting wheel as the tool drum with cutting discs arranged around the periphery of the cutting wheel are known, for example, from U.S. Pat. No. 4,548,442 or U.S. Pat. No. 5,234,257.
The present disclosure is based on a mining machine as well as a method according to WO 2010/050 872 A1. The corresponding machine is provided both for driving in tunnels and also in general for mining excavation, and works like the other known tunnel boring machines with a tool drum rotating about a drum axis and having on its periphery a number of radially outwardly directed spread-out excavating tools in the form of cutting discs. By means of a cantilever arm fitted at its front end with the tool drum, and a pivotal device, with which the cantilever arm can be pivoted relative to the movable machine base frame, the material is cut away at the work front or at the head face in front of the cutting head by pivoting the cutting head to and fro. With the mobile mining machine known from WO 2010/050 872 A1, the cutting discs can freely rotate in their suspension. The cutting discs are arranged spread out over the periphery of the tool drum so that the rotational axes of some of the cutting discs are parallel to the rotational axis of the tool drum and the rotational axes of other cutting discs stand inclined to the rotational axis of the tool drum. Through the spread-out arrangement of a number of cutting discs, with each pivotal movement with each cutting disc material is to be cut out only partially. Hereby, the load on the individual cutting discs, and, thus, the wear on the excavating tools on the cutting wheel is kept down. The pivotal axis for the pivotal movement stands substantially perpendicular at least to the drive chassis of the machine base frame. The cantilever arm can be raised or lowered via a tilt cylinder in order to break down material with the cutting wheel at different heights or banks. According to one embodiment, the pivotal movement of the tool drum takes place along an arc face, which is formed at the front end of the cantilever arm. Furthermore, a configuration of a mining machine is disclosed in WO 2010/050 872 A1 wherein two or three cutting wheels are provided. These cutting wheels can then each be pivoted inwards and outwards about a pivotal bearing relative to the machine base frame. The individual cutting wheels are thereby to be suspended from a frame, which can be turned about the tunnel longitudinal axis in order, by rotating the frame which holds the numerous cutting wheels, to be able to drive a tunnel in and forward with the oppositely movable cutting wheels, which themselves can only be pivoted perpendicular to the rotational axis of the tool drum.
In addition to driving in tunnels with in principle passively operating cutting discs, from US 2010/0001574 A1 or U.S. Pat. No. 7,631,942 B2 of the applicant, milling or drilling mining machines are also known having self-rotating excavating tools, which are mounted on a rotatable drum. The actual excavating tools on those mining machines consist of individual chisel tips which rotate with mostly high rotational speed about the rotational axis of a tool holder wherein the tool holder is fitted with several tool chisels. By rotation of the tool drum, only individual chisels of one tool holder have short term contact at the same time with the rock, which is to be excavated. Since with these mining machines only some few chisel tips or only one single chisel tip is/are in contact with the rock, which is to be excavated, a relatively low contact pressure force is necessary although a high excavating force can still be achieved.
The object of the present disclosure is to provide a mobile mining machine with which tunnels, galleries or shafts can be driven in or advanced even in hard rock with a high mining output and low tool wear.
Moreover, the present disclosure is directed, at least in part, to improving or overcoming one or more aspects of prior systems.